Figure 1.

Ets-2 (A72/A72) mice are protected from bleomycin-induced pulmonary fibrosis. Ets-2 (wild-type/wild-type [WT/WT]) and ets-2 (A72/A72) mice were treated with bleomycin (0.035 U/g) or PBS (vehicle control) for 33 days, as described in Materials and Methods. (A) After the mice had been killed, the lungs from bleomycin-treated mice were formalin-fixed, sectioned, and stained with hematoxylin and eosin (H&E) (top) or Masson's trichrome (bottom). Data represent the mean ± SEM of at least three mice per condition. (B) Murine lungs were used to quantitate collagen content, using the Sircol collagen assay. Data represent the mean ± SEM of at least three mice per condition. (C) After the mice were killed, their bronchoalveolar lavage fluid was analyzed for active TGF-β via ELISA. Data represent the mean ± SEM; n = 6 for ets-2 (WT/WT) + bleomycin; n = 8 for ets-2 (A72/A72) + bleomycin. A post hoc power analysis on TGF-β indicated that the power to detect this difference was 23%. (D–G) RNA from murine lungs was isolated, and mRNA was amplified and used for real-time PCR for Type I collagen (D), Type III collagen (E), connective tissue growth factor (CTGF) (F), and α–smooth muscle actin (α-SMA) (G). Data represent the mean ± SEM. n = 2 for ets-2 (WT/WT) + PBS; n = 5 for ets-2 (A72/A72) + PBS; n = 5 for ets-2 (WT/WT) + bleomycin; n = 7 for ets-2 (A72/A72) + bleomycin.